Sheet feeding mechanism for typewriters or like machines



Ot. 23, 1956 E. A. GlROUAl QD ETAL 2,767,821

SHEET FEEDING MECHANISM FOR TYPEWRITERS OR LIKE MACHINES Filed March 29.1954 2 Sheets-Sheet 1 III III i INVENTORS w m 0 m A M M f MW s.

w E N w n A Oct. 23,1956 E. A. GIROUARD ETAL ,7

SHEET FEEDING MECHANISM FOR TYPEWRITERS OR LIKE MACHINES 2 a mm Mn e 0A0E h TU]. N 4 m s w F W o e m N m A 0 S R 2 M Y m 5 United States PatentSHEET FEEDING MECHANISM FOR TYPE- WRITERS OR LIKE MACHINES Edgar AdelardGirouard, Marlborough, and John Felix Kloski, Hartford, Conn., assignorsto Royal McBee Corporation, a corporation of New York Application March29, 1954, Serial No. 419,304

11 Claims. 01. 197-138) This invention relates to sheet feedingmechanisms for typewriting and like machines and more particularly toimproved pressure roll construction and to improved pressurecoordination between the paper feeding cylinder and the pressure rolls.

Conventional typewriters of the kind including a rotatable sheet feedingcylindrical platen customarily include a paper pan extending under andcircumferentially with respect to the platen for guiding and holdingwork sheet material against the platen, and pressure rolls engaging thework sheets for pressing them against the platen. While many such priorconstructions have been generally satisfactory in operation, specificdifficulties sometimes are encountered with respect to creeping of thework sheets lengthwise of the platen with consequent wrinkling due tothe slack in the work sheets between the feed pressure rollers,sometimes even causing the work sheets to tear and to become misalignedwith the platen.

When a paper pack composed of work sheets and carbon paper isinterleaved for the purpose of making multiple copies in a single typingoperation, it frequently occurs that the pressure rolls of conventionalmachines press so forcibly against the platen that carbon is transferredfrom the carbon papers to the work sheets at those points where thepressure rolls bear against the paper pack. This results in unsightlysmudged copies which is an undesirable characteristic of conventionaltypewriters.

An object of the present invention is to provide an improved sheetfeeding construction including a sheet feeding cylinder and a pluralityof rolls arranged to press work sheet material against the cylinder incircumferentially spaced zones, the rolls having different sheetforwarding or feeding characteristics so related as to eliminate orreduce such difiiculties to a minimum.

Another object of the invention is to provide a construction of the kindreferred to in which the pressure exerting rolls have different frictioncharacteristics.

Another object of the invention is to provide a sheet feedingconstruction in which pressure rolls spaced circumferentially of acooperable sheet feeding cylinder are forced against or toward thecylinder with differential pressures so related as to eliminate orreduce the difiiculties heretofore encountered.

Another object of the invention is to provide an improved individualpressure roll construction.

Another object of the invention is to provide an improved relationbetween the position of the pressure rolls and the pressures exertedthereby against the platen.

Other objects and advantages of the invention will be specificallypointed out or will become apparent from the following description andclaims when considered in conjunction with the accompanying drawings inwhich:

Figure l is a fragmentary vertical sectional view, fore and aft of atypewriter carriage, taken along the line 11 of Figure 3, and showinginterleaved work sheets and carbon paper at the point of introduction tothe machine;

Figure 2 is a view similar to Figure 1, some parts being shown inelevation while other parts are omitted for the sake of clarity toillustrate interleaved work sheets and carbon paper in feeding relationin the machine;

Figure 3 is a top plan view of the carriage with the platen and worksheets removed, certain parts being shown in section;

Figure 4 is a fragmentary, enlarged transverse crosssection taken on theline 44 of Figure 1;

Figure 5 is an exploded, enlarged, perspective view of a pressure feedroller constructed in accordance with the invention; and

Figure 6 is an exploded, enlarged, perspective view of another pressurefeed roller.

The invention may be embodied in typewriters or like machines ofdifferent constructions. For the purposes of illustration it is shown asbeing incorporated in a standard or ofiice typewriter having some of theconventional parts customarily included in the Royal Standardtypewriter. Among the known parts shown is a platen or work sheetfeeding cylinder A journalled for rotary work sheet feeding movements bysuitable bearings (not shown) on end plates 1 and 2 of a carriage orsupport frame generally designated B. The support B includes a rail 3adapted to be supported by and to roll on balls 4 which in turn aresupported by and roll on a rail 5 supported by a stationary main frame.

interposed between the sheet feeding cylinder A and the support rail 3is a paper pan generally designated C which preferably is of the typedisclosed in the patent to Kloski, No. 2,582,783, and which is supportedby the support end plates 1 and 2 in a suitable manner. A rear or worksheet introductory feed roll 6 and front pressure, work sheet propellingfeed rolls 7, 8 and 9, all of which are journalled for rotation about anaxis parallel to the axis of rotation of the cylinder A, are provided tocooperate with the paper pan C for guiding and assisting in the feedingof work sheet material D into operative relation to the sheet feedingcylinder A. A paper finger guide 10 is adjustably mounted on thestationary frame by means of a nut and bolt assembly 11 the bolt ofwhich extends through a slot in a bracket 12 fixed to the sta tionaryframe rail 5. A plurality of top sheet positioning rolls, one of whichis shown at 15 in Figure 1, may be carried by a bail 16 pivoted on endplates 1 and 2 and arranged to aid in holding work sheets against thefront of the sheet feeding cylinder A. As so far described, theillustrated construction is conventional. The invention resides in therelation of the characteristics of the introducing roll 6 and thepropelling rolls 7, 8 and 9, the top rolls 15, and in the relativepressures by which the introducing and propelling rolls press againstthe sheet feeding cylinder.

The rear or work sheet introducing roller 6 comprises an elongatedsmoothly cylindrical tube 20 preferably formed from a hard substancewhich is smoothly polished so as to have a low coefficient of friction.Desirably, the composition of the tube 20 may be aluminum having aRockwell superficial hardness rating of 8283 (l5-T) or a Rockwell Bscale hardness rating of 66-68. An aluminum tube enables satisfactoryresults to be obtained, but aluminum is not to be considered as the solematerial from which the tube may be made as there are other metals andplastics which possess the desired qualifications as set forth. Ateither end of the tube 20, an oilite or nylon bearing 21, 22 may bepress fitted into the tube to journal the tube 20 on a shaft 23 whichpasses through and projects beyond the ends of the bearings. Thethreaded ends of the shaft 23 are received in notches for-med in leftandright-hand hanger arms 24 and 25, respectively, and are provided withnuts 18, 19 to prevent motion of the shaft laterally of the machine. Thehanger arms are pivotally mounted by means of pivot pins 29 on cars 26and 27 struck out from a cross bar 28 carried by the end plates 1 and 2of the support B. Also on the cross bar 28 are mounted flat springs 30and 31 whose ends bear against the rear edges of arms 24 and 25,respectively, to urge the arms clockwise, as viewed in Fig ures 1 and 2,to press the work sheet introducing roll 6 against the work sheetmaterial D extending between the introducing roller and the work sheetfeeding cylinder A. The total pressure or force applied to each of thehanger arms 24 and 25, and hence the total pressure urging theintroducing roller 6 against the sheet feeding cylinder A, may beregulated by means of adjusting nuts, one of which is shown at 32 inFigure 4, bearing against the rear surfaces of springs 30 and 31 andmounted on bolts 33 and 34 which project through openings in the crossrail 28 and through openings in the springs 30 and 31. To increase thetotal pressure exerted by the introducing roll 6 against the cylinder A,the nuts are run up on the bolts 33 and 34 which causes the springs 30and 31 to exert a greater rocking effort on the hanger arms 24 and 25,respectively, the rocking efifort being exerted in a clockwise directionas viewed in Figures 1 and 2. To reduce the total pressure exterted bythe introducing roller against the cylinder, this operation should bereversed.

To enable the work sheet introducing feed roller 6 to be released, thatis, moved away from the cylinder A against the force of the springs 30and 31 so as to facilitate the insertion of work sheets, one end of ashaft 36 is rockably mounted at 37 in a bracket 38 carried by thesupport rail 3 as shown in Figure 3, the other end of the shaftprojecting through a bearing (not shown) in the support end plate 2 andcarrying a gear 39. A lever 40, pivoted as at 41 on the end plate 2,carries at one end a toothed segment 42 whose teeth mesh with the teethof the gear 39. The other end of the lever 40 is equipped with a fingerpiece 43 to aid in rocking the lever 40. Rocking of the lever 40 causesthe toothed segment 42 to rock the gear 39, and, consequently, shaft 36also is rocked. Each hanger arm 24, is extended downwardly and forwardlybeyond the shaft 36 to provide respectively finger parts 45, 46, each ofwhich is received in a recess 47 formed in the shaft 36. Normally, whenthe parts are in the positions shown in Figure 1, 2 and 3, the fiatbottoms of the recesses 47 are aligned with the arm finger extensions45, 46, and are spaced from the fingers so as to enable the arms 24 and25 to be urged clockwise by the springs and 31 without being restrainedby the shaft 36. When it is desired to move the feed roll 6 rearwardly,the shaft 36 is rocked by means of the lever 40 and the cooperatingtoothed segment 42 and gear 39 so as to cause the bottoms of therecesses 47 to press against the fingers 45, 46 and thereby rock thehanger arms 24, 25 counterclockwise against the force of the springs 30,31.

An important feature of this invention resides in the relation betweenthe force or total pressure utilized to press the work sheet introducingfeed roller 6 against the sheet feeding cylinder A and the forceor'pressure with which the rolls 7, 8 and 9 are pressed against thecylinder A. As will be clear from the foregoing description, the soleforce tending to press the roll 6 against the cylinder is the forceapplied to the rear edges of the hanger arms 24, 25 through the springs30, 31. As has been pointed out, the force applied to the hanger armsthrough the springs may be varied by the adjusting nuts 32. Thisinvention contemplates utilizing, in an office typewriter of the generalclass referred to, a total pressure or force of not more than one andone-half pounds to urge the roller 6 against the cylinder A, and,preferably, the total pressure or force will be in the range of one andone-fourth to one and one-half pounds.

Total pressures within the range specified are considerably less thancustomarily are utilized for feed rollers located in conventionalmachines in a position corresponding to the roller 6. The lower totalpressure acting on therollcr' 6 together with its smooth, polishedsurface changes the function of the roller 6 from primarily a sheetfeeding roller to primarily a sheet aligning and guiding means, and,secondarily, the initial work sheet advancing means, coacting with thesheet feeding cylinder A and assisting in introducing work sheetmaterial between the paper pan C and the sheet feeding cylinder A.Hence, the roll 6 has been termed a work sheet introduc' ing roll ratherthan a work sheet feeding roller. Work sheets are fed or propelled bythe cooperation of the sheet feeding cylinder A and the front pressurerolls 7, 8, and 9 as will be more specifically pointed out.

The front pressure of work sheet propelling rolls 7, 8 and 9, comprise aplurality of short, soft, resilient, thiclo walled tubes 50, 51, 52,having a high coefiicient of friction. A suitable substance from whichthe tubes may be formed is rubber having a durometer hardness ratingwithin the range of 4050; and the thickness of the walls of the tubesmay be substantially equal to the radius of the bore. A tube formed ofrubber in accordance with these specifications has a highly frictionalsurface and may be compressed substantially without causing excessivehardening of the rubber due to compacting. The substance of which thetubes are formed is preferably much softer than the substance whichforms the outer surface of the cylinder A, which latter substance may bethe conventional hard rubber.

In the embodiment of the invention shown, the tubes 50, 51, 52 arecemented to sleeves 53 whose ends are equipped with press fitted bronzebushings 54 journalled on a shaft 55. The shaft 55 is carried by spaced,short arms 56, 57, and 58, the short arms being rockable in unison onstub shafts 59, 60 and 61 secured to the support rail 3. As shown, thestub shafts fit into recesses formed in the support rail and are held inplace by retaining plates 62, 63, 64, secured to the rail 3 by screws65, 66, 67. Each plate is provided with a flange as shown at 68, 69, 70adapted to fit into a correspondingly positioned recess formed in thesupport B so as to position the plates accurately on the rail 3.Although not shown in the drawings, the support rail 3 is provided withtransversely extending slots in which the arms 56, 57, 58 are receivedtoipermit mounting of the arms on the stub shafts 59, 60, 61 withoutinterference from the rail 3.

Separate and independently adjustable mechanisms E are provided forurging the arms 59, 60, 61 to rock clockwise as viewed in Figures 1 and2, so as to cause the feed rolls 7, 8 and 9 to press against the worksheet material D extending between the feed rolls and the sheet feedingcylinder A. The mechanisms E may be of any suitable type, and in theform of the invention illustrated, they are of the kind disclosed in thepatent to Kloski, No. 2,582,783.

Each mechanism E is similar to the other mechanisms E, and accordingly,only one mechanism will be described. A mechanism E comprises atwo-armed lever 75 mounted to rock on a pivot screw 76. One arm 77 ofthe two armed lever 75 is formed with a rounded edge which projectsunder and is in contact with the arm 56, 57 or 58 supporting the shaft55. The other arm 78 of the lever 75 is apertured for connection to oneend of a spring 79, the other end of which is connected to a springanchor 80 in the form of a twoarmed lever pivoted on a screw 81. Asshown in Figure 3, one arm 82 of the spring anchor lever 80 is aperturedfor connection to the spring '79, and the other arm 83 of the lever 80is formed with a rounded edge which is engaged by an end of an adjustingscrew 34 which has threaded connection with an car projecting upwardlyfrom support rail 3.

Tension imposed on the springs 79 by rocking the levers 80 by theadjusting screws 84 causes the levers 75 to be rocked about the pivotscrews 76 so as to raise the arms 56, 57, 58, which in turn raise theshaft 55 thereby more forcibly pressing the feed rollers 7, 8, and 9against the sheet feeding cylinder A. Conversely, to lessen the pressureexerted on the cylinder A by the feed rollers 7. 8

and 9, the screws 84 are backed off, thus permitting reverserotationof'levers 80, as viewed in Figure 3, which lessens the tension ofsprings 79. In order that the work sheet propelling rollers 7, 8 and 9may be retracted so as to permit work sheets easily to be insertedbetween the rolls and the cylinder A or to be withdrawn, the arms 56, 57and 58 are formed with extensions 85, 86 and 87 which normally extendfreely into slots 88 formed in the shaft 36. When the shaft 36 is rockedby the lever 40 and the cooperating toothed segment 42 and gear 39, forreleasing or retracting the work sheet introducing roll 6, the bottomsof the slots 83 will press against the arm extensions 85, 86 and 87 torock the arms 56, 57, and 58 counterclockwise as viewed in Figure 1,thereby moving the rolls 7, 8 and 9 away from the cylinder A. I

The top or bail rolls, one of which is shown at in Figure 1, preferablyare formed of material the same as that-specified for the work sheetpropelling rollers 7, 8 and ,9, so that the rolls 15 may press againstthe work sheets to hold and guide them but, due to the resiliency of theroller material will not cause a transfer of carbon from interleavedcarbon paper to the subjacent work sheets.

To accomplish the objects of the invention, when embodied in atypewriter of the character referred to and in which the pressureexerted on the rear roll 6 is of the order herein above indicated, thetension of the springs 79 should be set so that the total pressure orforce exerted by the rolls 7, 8 and 9 against the cylinder A is not lessthan one and three-quarter pounds, and, preferably, within the range ofone and three-quarter pounds to two pounds. By the term total pressureis meant the force required to withdraw the shaft 55, with the rolls 7,8 and 9 mounted thereon, away from the cylinder A against the force ofthe springs 79. The term total pressure as applied to the introducingroller 6 means that the total force required to withdraw roller 6 fromcontact with cylinder A, against the force of Springs 30 and 31, shouldbe within the range specified, namely: one and one-fourth 'to one andone-half pounds.

"In a typical commercial construction embodying the invention the worksheet feeding cylinder has a length of approximately nine andseven-eighths inches and a diameter of approximately one and one-halfinches. The rear or introducing roll means 6 is approximately six andthree-quarters inches in length and has an approximate diameter ofeleven-sixteenths inch. In the illustrative embodiment, the forwardingroll means 6 comprises a single or one piece roller. The propelling rollmeans is shown "as comprising three rollers 7, 8 and 9 the total lengthof which is approximately three and one-sixteenth inches and thediameter of each roller 7, 8 and 9 is approximately three-eighths inch.When rollers having these approximate measurements are located as shownin the drawings with a greater total pressure applied to the shorterrollers than is applied to the longer roller, the unit pressure exertedby the small short rollers will be greater than the unit pressureexerted by the larger longer roller due both to the greater area ofcontact of the larger roller,

.fourth pounds and the rear feed roller having the normal total pressureapplication of two to two and one-fourth pounds. A paper pack composedof one sheet of bond paper, four sheets of manifold paper, and foursheets of carbon paper interleaved with the manifold paper wasintroduced into the typewriter between the feed rollers and the cylinderor platen. Near the upper left hand edge of the paper pack, the word Thewas typed. Following the typing of the upper left The the carriage andpaper pack were letter spaced to the left and a second The was typednear the upper right hand edge of the paper. The paper pack then wasadvanced through the typewriter a certain number of lines and the wordThe typed near the lower left hand edge of the paper, this The beingpositioned in vertical alignment but below the upper left The. Thecarriage and paper pack then were letter spaced to the left and a fourthThe typed, this The appearing in vertical alignment and below the upperright The. Following the typing of the fourth The the paper pack was fedreversely through the machine the same number of line spacing incrementsit had been advanced forwardly and the word The was typed for a fifthtime, this The being typed at a position on the paper which shouldcorrespond to the position of the first typed or upper left The. Thenthe word The was typed for a sixth time near the upper right hand edgeof the paper in a position which should correspond to the position ofthe second typed The. Had there been no slipping of the paper pack inthe typewriter, the fifth and sixth typed Thes should have beensuperimposed perfectly on the first and second typed Thes, respectively.Instead of being in perfect register with the first and second typedThes however, the fifth and sixthtyped Thes were vertically displacedrelatively to the first and second typed Thes, the fifth type Theappearing above the first typed The and the sixth typed The appearingbelow the second typed The. Moreover, the fifth and sixth typed Theswere disposed slightly to the left of the first-and second typed Thes,respectively. The results of this test indicate both slipping andcreeping of the paper pack in the machine. On the manifold sheetsforming part of the paper pack, none of the Thes was superimposed, and,in addition, the pressure feed rolls had caused carbon from the carbonpaper to transfer to the manifold sheets where the pressure rolls hadpressed against the paper pack, leaving messy, unsightly carbon streaksor smudges on the manifold sheets.

In a comparative test, the same typewriter used in the first test justdescribed was used, with the exception that the conventional feed rollsand top or bail rolls were replaced by the metal rear feed orintroducing roll and the soft rubber propelling and top rolls urgedtoward the cylinder by forces in accordance with the specifications setforth herein. A paper pack identical in every respect to the one used inthe first test was inserted in the typewriter and the test performed ina manner identical to that of the first test. The results of the secondtest disclosed that the first and fifth typed Thes, that is, those nearthe upper left-hand edge of the paper, were superimposed perfectly andthat the second and sixth typed Thes were so nearly perfectlysuperimposed as to be practically in perfect register. The same resultswere obtained on the manifold sheets with the additional advantage thatthe transfer of carbon to the manifold sheets was practicallyeliminated. The results of the sec-0nd test indicate that the improvedroller constructions mounted in accordance with the total pressurevalues specified herein practically eliminate the objectionablecharacteristics of known machines.

In the second test, the work sheet introducing roll means was urgedtoward the sheet feeding cylinder under a total force of one andone-fourth to one and one-half pounds,

and the work sheet feeding or forwarding roll means was urged toward thecylinder under a total force of one and three-fourths to two pounds. Itis not necessary in all cases to use force or pressure values, eithertotal or unit, the same as those herein set forth, but the forces actingon the introducing roll means and the forwarding roll means, and thefrictional characteristics of the roll means should be related generallyin accordance with the foregoing disclosure. The construction disclosedby way of example embodies the invention in a preferred form but it isintended that the disclosure be illustrative rather than definitive. Theinvention is defined in the claims.

We claim:

1. In a typewriting or like machine, a support; a cylinder journalled onsaid support for rotary work sheet feeding movements; a first roller,said first roller having a smoothly cylindrical relatively friction freesurface thereon; means mounting said first roller for rotation about anaxis parallel to the axis of said cylinder and so spaced therefrom thata work sheet extending between said cylinder and said first roller isgripped therebetween with a relatively low pressure; a second roller,said second roller having a frictional surface thereon; and meansmounting said second roller for rotation about an axis parallel to theaxis of said cylinder and so spaced therefrom that a work sheetextending between said cylinder and said second roller is grippedtherebetween with a relatively high pressure as compared with thepressure exerted by said first roller, said second roller beingcircumferentially displaced with respect to said cylinder from saidfirst roller.

2. in a typewriting or like machine, a support; a cylinder journalled onsaid support for rotary work sheet feeding movements; a work sheetintroducing roller, said introducing roller having a smoothlycylindrical relatively friction free surface thereon; means mountingsaid introducing roller for rotation about an axis parallel to the axisof rotation of said cylinder and so spaced therefrom that a work sheetintroduced between said cylinder and said introducing roller is grippedtherebetween with a relatively low pressure; a work sheet propellingroller, said propelling roller having a frictional surface thereon; andmeans mounting said propelling roller for rotation about an axisparalell to the axis of said cylinder and so spaced therefrom that awork sheet extending between said propelling roller and said cylinder isgripped therebetween with a relatively high pressure as compared withthe pressure exerted by said introducing roller, said propelling rollerbeing circumferentially displaced with respect to said cylinder fromsaid introducing roller in the direction of sheet feeding.

3. In a typewriting or like machine, a support; a cylinder journalled onsaid support for rotary work sheet feeding movements; a smoothlycylindrical hard surfaced first roller; means mounting said first rollerfor rotation about an axis parallel to the axis of said cylinder and sospaced therefrom that a work sheet extending between said cylinder andsaid first roller is gripped therebetween with a relatively lowpressure; a soft surfaced second roller; and means mounting said secondroller for rotation about an axis parallel to the axis of said cylinderand so spaced therefrom that a work sheet extending between saidcylinder and said second roller is gripped therebetween with arelatively high pressure as compared with the pressure exerted by saidfirst roller, said second roller being circumferentially displaced withrespect to said-cylinder from said first roller.

4. In a typewriting or like machine, a support; a cylinder journalled onsaid support for rotary work sheet feeding movements; a work sheetintroducing roller, said introducing roller having a smoothlycylindrical hard relatively friction free surface thereon; meansmounting said introducing roller for rotation about an axis parallel tothe axis of rotation of said cylinder and so spaced therefrom that awork sheet introduced between said cylinder and said introducing rolleris gripped therebetween with a relatively low pressure; a work sheetpropelling roller, said propelling roller having a soft frictionalsurface thereon; and means mounting said propelling roller for rotationabout an axis parallel to the axis of said cylinder and so spacedtherefrom that a work sheet extending between said propelling roller andsaid cylinder is gripped therebetween with a relatively high pressure ascompared with the pressure exerted by said introducing roller, saidpropelling roller being circumferentially displaced forwardly in thedirection of sheet feeding with respect to said cylinder from saidintroducing roller.

5. in a typewriting or like machine, a support; a cylinder journalled onsaid support for rotary work sheet feeding movements; a smoothlycylindrical hard surfaced first roller; means mouting said first rollerfor rotation about an axis parallel to the axis of said cylinder and sospaced therefrom that a work sheet extending between said cylinder andsaid first roller is gripped therebetween a relatively low pressure; asoft surfaced second roller; means mounting said second roller forrotation about an axis parallel to the axis of said cylinder and sospaced "rom that a work sheet extending between said cylinand secondroller is gripped therebetween with a relatively high pressure ascompared with the pressure exerted by said first roller, said secondroller being circutnferentially forwardly displaced in the direction ofsheet feeding with respect to said cylinder from said first roller; abail mounted on said support for swinging mover ment about an axisparallel to the axis of said cylinder; and a work sheet pressing rollercarried by said bail and swingable therewith into and out of pressingengagement with said cylinder, said work sheet pressing roller having asoft frictional surface.

6. in a typewriting or like machine, a support; a cylinder iournalled onsaid support for rotary work sheet feeding movements; a work sheetintroducing feed roller having a smoothly cylindrical, polished,relatively friction free surface and composed of a material having aRockwell B scale hardness within the limits of 66 to 68, inclusive;means mounting said introducing roller for rotation about an axisparallel to the axis of said cylinder and so spaced therefrom that awork sheet introduced between said cylinder and said introducing rolleris gripped therebetween with a relatively low pressure; a work sheetpropelling roller having a surface composed of a material having a highcoefiicient of friction and havinga durometer hardness within the limitsof 40 to 60, inclusive; and means mounting said propelling roller forrotation about and axis parallel to the axis of rotation of saidcylinder and so spaced therefrom that a work sheet extending betweensaid propelling roller and said cylinder is gripped therebetween with arelatively high pressure as compared to the pressure exerted by saidintroducing roller, said propelling roller being circumferentiallydisplaced with respect to said cylinder from said introducing roller.

7. A typewriting or like machine as set forth in claim 6 wherein theratio between the pressures exerted on said first and second rolls arein the relation of the total pressure exerted on a work sheet betweensaid introducing roller and said cylinder being not more than one andone-half pounds and the total pressure exerted on a work sheet betweensaid propelling roller and said cylinder being not less than oneandthree-quarter pounds.

8. A typewriting or like machine as set forth in claim 7 including abail mounted on said support for swinging movement about an axisparallel to the axis of said cylinder; a work sheet pressing rollercarried by said bail and swingable therewith into and out of pressingengagement with said cylinder, said work sheet pressing roller having asoft frictional surface.

9. In a typewriter or like machine, a support; a cylinder journalled onsaid support for rotary work sheet feeding movements; work sheetintroducing smoothly cylindrical roller means; means mounting saidintroducing roller means for rotation about an axis parallel to the axisof rotation of said cylinder and so spaced therefrom that a work sheetintroduced between said cylinder and said introducing roller means isgripped therebetween; work sheet propelling roller means; and meansmounting said propelling roller means for rotation about an axisparallel to the axis of rotation of said cylinder and so spacedtherefrom that a work sheet extending between said cylinder and saidpropelling roller means gripped therebetween, said introducing rollermeans ogether with said cylinder constituting means for initially cedingwork sheet material introduced to said typewriter or like machine, saidpropelling roller means being cir cumferentially displaced in thedirection of sheet feeding with respect to said cylinder from saidintroducing roller means, the relative frictional sheet feedingcharacteristics of said propelling roller means and said introducingroller means being such that the sheet feeding tendency of saidpropelling roller means is greater than the sheet feeding tendency ofsaid introducing roller means.

10. In a typewriter or like machine, a support; a cylinder journalled onsaid support for rotary Work sheet feeding movements; work sheetintroducing smoothly cylindrical roller means; means mounting saidintroducing roller means for rotation about an axis parallel to the axisof rotation of said cylinder and so spaced therefrom that a work sheetintroduced between said cylinder and said introducing roller means isgripped therebetween; Work sheet propelling roller means; and meansmounting said propelling roller means for rotation about an axisparallel to the axis of rotation of said cylinder and so spacedtherefrom that a work sheet extending between said cylinder and saidpropelling roller means is gripped therebetween, said introducing rollermeans together with said cylinder constituting means for initiallyfeeding work sheet material introduced into said typewriter or likemachine, said propelling roller means being circumfcrentially displacedin the direction of sheet feeding with respect to said cylinder fromsaid introducing roller means, the relative frictional sheet feedingcharacteristics and the relative spacing of said propelling roller meansand said introducing roller means being such that the sheet feedingtendency of said propelling roller means is greater than'the sheetfeeding tendency of said introducing roller mean-s.

11. In a typewriter or like machine, a support; a cylinder journalled onsaid support for rotary work sheet feeding movements; a smoothlycylindrical Work sheet introducing roller; means mounting saidintroducing roller for rotation about an axis parallel to the axis ofrotation of said cylinder and so spaced therefrom that a work sheetintroduced between said cylinder and said introducing roller is grippedtherebetween with a relatively low pressure; a work sheet propellingroller; and means mounting said propelling roller for rotation about anaxis parallel to the axis of said cylinder and so spaced therefrom thata work sheet extending between said propelling roller and said cylinderis gripped therebetween with a relatively high pressure as compared withthe pressure exerted by said introducing roller, the ratio between thepressure exerted by said first roller on a work sheet between said firstroller and said cylinder and the pressure exerted by said second rolleron a work sheet between said second roller and said cylinder beingapproximately one and one-half to one and three-quarters, saidpropelling roller being circumferentially displaced with respect to saidcylinder from said introducing roller in the direction of sheet feeding.

References Cited in the file of this patent UNITED STATES PATENTS975,228 Gibbs Nov. 8, 1910 1,247,456 Schwartz Nov. 20, 1917 1,367,784Kurowski Feb. 8, 1921 1,444,385 Phelps Feb. 6, 1923 2,328,624 DodgeSept. 7, 1943

